1. Field of the Invention
The invention relates to signs and more particularly, to an improved, adjustable display panel for back-lighted signs.
2. Description of the Related Art
Back-lighted signs are frequently used for advertising and promotion. Generally, in a back-lighted sign, an opaque message and/or picture is secured within a display panel. The display panel is typically mounted to a housing which includes a front wall, a rear wall, a top wall, a bottom wall and two side walls, wherein the top, bottom and side walls are peripherally joined to the front and rear walls, thereby defining a cavity within the housing. The front wall typically includes an aperture therein so that a light mounted within the cavity may shine through the aperture and illuminate a display panel attached to the front wall. The light illuminates the display panel and accentuates the message/picture on the display panel during the day and illuminates the message/picture at night.
Back-lighted signs, of the type described above, are typically found above counters in fast food restaurants. Often, such signs consist of a number of display panels with each panel displaying a different category of menu items and corresponding prices. For example, one panel may list hot sandwiches, with another panel for cold sandwiches, and yet another panel may list beverages and desserts. A display panel may also display a photographic reproduction of a food item being offered for sale in order to create customer interest.
Because display areas vary from restaurant to restaurant, and because of a need to create a distinctive appearing sign for different restaurants, modular sign systems have been devised. Such sign systems are typically created by attaching side-by-side a number of square, or rectangular, sign modules, each having a housing which contains lightbulbs for illuminating a translucent display panel attached to a front wall of the housing. Such rectangular modules can be combined horizontally or vertically, or in a two-dimensional array to form different sized and shaped sign assemblies. An example of such a modular sign system is disclosed in U.S. Pat. No. 5,379,540 to Howard, entitled "MODULAR SIGN SYSTEM."
However, even with the above-described modular sign system, within a single given sign module, the display cannot easily be changed. Typically, within each display panel a specified number of image slides and/or photographic gels (referred to as "sign elements" herein) are inserted into a frame which surrounds a specified number of display windows, each configured to hold an individual sign element. For each of these display panels, the number of display windows and the size of each display window is fixed, or at the very least, extremely cumbersome to alter. Therefore, within a single given sign module, the number of items that may be displayed is not easily changed. Additionally, if one desires to change the size of a particular sign element, the old display panel must be replaced by a new display panel having a display window which matches the size of the desired sign element, or the frame of the display panel must be completely dismantled and reconfigured to provide the appropriately sized display window. These prior art display panels are not designed and constructed to be altered after the first time they have been assembled. Therefore, changing the configuration of the display windows within these display panels is tedious and time consuming.
One example of a prior art display panel is illustrated and disclosed in U.S. Pat. No. 4,277,904 to Leuthesser, entitled, "Back Lighted Sign Frame." Leuthesser discloses a frame which surrounds a specified number of display windows, each display window capable of displaying a desired advertisement or other image therein. Multiple display windows may be created by dividing a particular display window with a partitioning member. However, once this display panel is created, it is not designed to be altered. Leuthesser discloses that each partition member is secured to the frame by means of tabs which extend longitudinally outwardly from each end of the partitioning member to be inserted into slots located on the frame. Leuthesser further discloses "suitable glue or other adhesive applied to the tabs to secure the [partitioning] member in the proper position . . . ." However, even without glue or adhesive, in order to remove a particular partitioning member from the frame of the display panel disclosed by Leuthesser, one must flex and/or bend the partitioning member so as to dislodge the tabs attached to the ends of the partitioning member from their respective slots. This process often results in bent, broken, or otherwise damaged partitioning members and, additionally, is a clumsy and tedious process to undertake. Furthermore, the process of removing the partitioning members sometimes causes damage to the peripheral frame itself.
Therefore, prior art display panels do not provide a fully satisfactory method or system for adjusting the display panel so as to receive and display different sizes and/or numbers of sign elements. Therefore, there is a need to provide an adjustable display panel which may be quickly and easily modified so as to be able to accommodate different sizes and/or numbers of sign elements, as menu items change, for example.
Another deficiency of prior art display panels relates to the sign elements themselves. These sign elements are typically sheets of plastic material which are die cut and stamped into a desired geometirc configuration and have printed onto them a desired logo, name, message, etc. The sign elements are typically translucent such that they may be illuminated by a light source which shines light onto the backside of the sign element. Prior art sign elements typically consist of a front piece which is a rectangular-shaped plastic sheet having an image printed thereon. The front piece is permanently attached to a back piece which is a congruently shaped plastic sheet typically having a white, or off-white, color. Typically, the front piece includes multiple windows cut therein for allowing alphanumeric characters to be displayed therethrough. Pockets are formed between the first and second pieces at positions corresponding to the windows cut in the front piece. The pockets are typically formed by placing strips of double-sided adhesive tape between the front piece and back piece such that a pocket is defined between two adjacent strips which are laterally positioned across the width of the front and back pieces. The thickness of the double sided adhesive tape and the space between adjacent strips define the geometry of a respective pocket.
In order to display a price for a menu item, for example, numerical inserts are inserted into the pockets, and each numeral printed on an insert is visible through a respective window cut in the front piece. If the price of that particular menu item is changed, it is a relatively simple matter to replace the numerical inserts with new numerical inserts. However, if a new menu item, altogether, is desired to be displayed within a particular display window, the entire sign element which displays the old menu item must be replaced with a new sign element which illustrates the new menu item. This is not cost effective because both the front and back pieces of the sign element must be discarded, and additionally, the pockets formed between the front and back pieces are also wasted. Although the formation of the pockets is not expensive in terms of materials required, it does require extra manufacturing time and processing to form the pockets, which significantly adds to the manufacturing cost for each sign element. On the other hand, the printing and cutting of only the front piece is a relatively simple process and may be performed automatically by any one of a number of well-known printing machines.
Therefore, when a sign element is to be changed, it is desirable to be able to replace only the front piece of the sign element while retaining the back piece and the pockets for further use. This would not only decrease the amount of wasted materials (e.g., plastic sheeting) to less than one half of previous amounts, but, additionally, would save a significant amount of manufacturing steps and processing time which would otherwise be required to form pockets between the front and back pieces of a sign element.